LEETCODE PATTERNS Solving problems with LeetCode Problems Title Solution Difficulty Contains Duplicate Solution Easy Missing Number Solution Easy Find All Numbers Disappeared in an Array Solution Easy Single Number Solution Easy Climbing Stairs Solution Easy Best Time to Buy and Sell Stock Solution Easy Range Sum Query - Immutable Solution Easy Counting Bits Solution Easy Linked List Cycle Solution Easy Middle of the Linked List Solution Easy Reverse Linked List Solution Easy Palindrome Linked List Solution Easy Remove Linked List Elements Solution Easy Two Sum Solution Easy Majority Element Solution Easy Running Sum of 1d Array Solution Easy Find Pivot Index Solution Easy Is Subsequence Solution Easy Isomorphic Strings Solution Easy Merge Two Sorted Lists Solution Easy Longest Palindrome Solution Easy N-ary Tree Preorder Traversal Solution Easy First Bad Version Solution Easy Binary Search Solution Easy Fibonacci Number Solution Easy Min Cost Climbing Stairs Solution Easy Fizz Buzz Solution Easy Ransom Note Solution Easy Number of Steps to Reduce a Number to Zero Solution Easy Linked List Cycle II Solution Medium Binary Tree Level Order Traversal Solution Medium